The equivalent is
std::wstring declared in the
<string> header file.
Though you should note that python has probably different intrinsic behavior about handling automatic conversions to UNICODE strings, as mentioned in @Vincent Savard’s comment.
To overcome these problems we use additional libraries in c++ like libiconv. It’s available for use on a broad number of platforms.
You should seriously note to do some better research before asking at Stack Overflow, or ask your question more clearly.
std::string is ubiquitous.